Digital clock with novel indexing drums

ABSTRACT

A DIGITAL CLOCK HAVING A PLURALITYOF DRUMS SHOWING THE HOURS AND MINUTES, AND A GENEVA MOVEMENT HAVING GEAR ELEMENTS AT THE PERIPHERY OF THE DRUMS, FOR GREATER ACCURACY AND POSITIONING OF THE DRUMS.

Oct. 12, 1971 E. J. NlZNlK DIGITAL CLOCK WITH NOVEL INDEXING DRUMS 2Sheets-Sheet 1 Filed Feb. 2, 1970 Oct. 12, 1971 E. J. NIZNIK DIGITALCLOCK WITH NOVEL INDEXING DRUMS 2 Sheets-Sheet 2 Filed Feb. 2, 1970l/Li/ fj w/ @ozmw lc &

United States Patent 01 hce 3,611,705 Patented Oct. 12, 1971 ABSTRACT OFTHE DISCLOSURE A digital clock having a plurality of drums showing thehours and minutes, and a Geneva movement having gear elements at theperiphery of the drums, for greater ac curacy and positioning of thedrums.

CROSS REFERENCES Applications of the same inventor filed of even dateherewith: Ser. No. 7,470, Digital Clock Second Indicator; Ser. No.7,471, Digital Clock.

OBJECTS OF THE INVENTION I A broad object of the invention is to providea digital clock construction including digital drums bearing timeindications, and novel Geneva movement construction for sequentiallyadvancing the drums in periodic movements.

Another object is to provide a digital clock construction of thecharacter just referred to in which the Geneva construction includesgears closely adjacent the periphery of the drums for providing greateraccuracy of movement and control and to minimize friction in themovements of the drums.

A further object is to provide a digital clock construction of theforegoing general character incorporating novel and effective lockingfeatures as between the adjacent drums.

A still further object is to provide in a digital clock constructionhaving a plurality of time indicating drums, in which the drums havenovel construction providing good visibility by transmitting internallight through transparent portions forming the time indications.

A still further object is to provide a digital clock construction of theforegoing general character in the operation of which a minimum of poweris required for advancing the drums.

DESCRIPTION OF A PREFERRED EMBODIMENT In the drawings:

FIG. 1 is a view of the clock mechanism of the invention as viewed fromthe top and showing various elements in section;

FIG. 2 is an elevational face view of the digital time indicating drums,which are shown in section at the left of FIG. 1;

FIG. 3 is a view taken at line 3-3 of FIG. 1;

FIG. 4 is a view taken at line 44 of FIG. 1;

FIG. 5 is a view taken at line 5 -5 of FIG. 1; and

FIG. 6 is a sectional view of a small portion of FIG. 1 indicated by thearrow 6 in that figure.

Certain portions of the disclosure in the present application areidentical with or similar to corresponding portions in the crossreference applications identified above, and the corresponding elementsand portions are given identical reference numerals in all theapplications.

In the present instance, FIG. 1 shows a crystal 10 forming a base orsupporting member supporting the remainder of the clock and serving as aprincipal means of mounting the clock in position, such as in anautomobile. On the base is a housing 12 substantially enclosing theoperating parts, and mounting an interior illuminating lamp 14 whichwill be referred to again hereinbelow. The clock construction includes asupporting panel 16 in which are a plurality of posts 20 supporting apair of spaced plates 22, 24, and mounted in the latter plate 24 areanother plurality of posts 26 supporting a mounting plate 28.

An electric motor 30 is provided for driving the clock mechanism inperiodic advancing movements. The motor 30 includes a drive shaft 36having a worm 38 meshing with a worm gear 40 on a shaft 42 having a gear44 in mesh with another gear 46 which in turn meshes with a gear 48. Thegear 48 is mounted on a shaft 50 having a gear 52 in mesh with anothergear 54 on a shaft 56- having a worm 57 in mesh with a gear 58. The gear58 is mounted on shaft means 59 operatively connected with a digitaltime indicating unit 60, this unit 60 and its specific construction,constituting a principal feature of the invention. This unit will bedescribed in detail hereinbelow.

Also included in the clock construction is a power transmitting ordriving unit 66 and escapement mechanism identified as a whole at 70.These two components or units 66, 70' are described in detail in thecross reference applications referred to above and it is believedunnecessary to include herein a description of the details thereof.Briefly, the gear 52 meshes with the gear 68, and thereby turns orrotates the latter at the same time that the time indicating drums inthe unit 60 are advanced. The unit 66 includes a torsion main spring 82that is tensioned by the rotation of the gear 68, and the unit 66continues to rotate a seconds indicator 126 and a control unit 78, underthe control of the escapement mechanism 70. At each rotation of the unit78 about the axis of the spring 82 the motor 30 is energized under thecontrol of the unit 78 and operates through a predetermined period,which in this instance is on the order of 3-4 seconds; the size andproportion of the gear train between the motor and the unit 78, andbetween the motor and the unit 60 are such that at each energization andcyclic operation of the motor, the unit 78 is rotated once around theaxis of the spring 82, and the time indicating unit 60 is advanced anincrement representing one minute, as referred to again hereinbelow. Theseconds indicator 126 is rotated constantly under the action of the coilspring 82 and under the control of the escapement mechanism 70, so thatthe indicator 126 makes one revolution or rotation per minute, and atthe end of each minute-cycle again controls the motor 30 for advancingthe time indicating drum unit 60* at that time, and energizing the coilspring 82. While details of operation of the control unit 66 aredescribed fully in the cross reference applications identified above, itis desired to state that an element of the shaft means 59 is rotated ateach minute interval, an increment representing one minute. The timeindicating unit 60 includes a minute drum 61, a ten-minute drum 62 andan hour drum 63. Preferably the minute drum 61 is provided with tendigits 1 to 9, and 0 distributed in a single series therearound; theten-minute drum 62 preferably includes two series of digits, each from 1to 5, and 0; and the hour drum 60 preferably includes a single series ofdigits of 1 to 12. These various drums are advanced at correspondingportions of the hour.

The shaft means 59 includes a shaft proper 138 fixedly mounted insupporting means of suitable and known kind. Rotatable on the shaft 138is a sleeve 144 carrying the minute drum 61. The ten-minute drum 62 andthe hour drum 63 are mounted on the shaft 138 for rotation relativethereto. The sleeve 144, with the drum 61, is rotated once each minuteunder the drive from the motor 30, through the gear 58, and the othertwo drums 62, 63 are rotated from the first one by means of a novelGeneva mechanism indicated in its entirety at 146 (FIG. 1).

The drums 61, 62, 63 may be of any suitable constructional shape, havingouter cylindrical peripheral elements 148 bearing the indicia 64 ontheir outer surfaces presented suitably to view, such as exposurethrough a window 65 (FIG. 2).

The drums of the unit 60 for purposes of incorporating the novel Genevamechanism 146 include construction as follows: the dum 61 (FIG. 3)includes a web in the form of spokes 149 forming openings 150therebetween, and an axially extending annular rib 151 (FIG. 1)telescoping into the element 148 in the next drum 62; the rib 151 on itsradially inner surface 152 is provided with two tooth elements 154 atone location (see also FIG. 3); the ten-minute drum 62 similarlyincludes a spoke-web 155 and an annular element 156 extending into theouter peripheral element 157 in the drum 63, and another annular element159 on the other side of the spoke-web 155 providing radially inwardlyfacing surfaces 160. The surface 158 is provided with a continuousseries of teeth 162 while the surface 160 is provided with two toothelements 168 (see also FIG. at each of two locations this arrangementcorresponding to the two series of digits on the outer surface of thatdrum; in a similar manner, the hour drum 63 includes the annular element157 mentioned having a radially inwardly directed surface 172 on whichis provided a continuous series of teeth 174.

The Geneva mechanism 146 includes a first unit 176 and a second unit 178substantially identical in construction.

Each Geneva mechanism component 176, 178, includes an arm 180 having anaperture 182 (FIGS. 3-5) receiving the shaft 138 and having a fiat 186locking the arms to the shaft against rotation. The arms extend radiallyoutwardly, and in the outer ends thereof are gear components, that onthe arm 180 including a first gear 188 and a second 190, and that on thearm 182 having a first gear 192 and a second gear 194.

In the case of the component 176 the gear element 188 is positionedwithin the annular element 151 for engagement by the tooth elements 154and the other gear element 190 is positioned within the surface 158 andmeshing with the continuous series of teeth 162.

In the case of the component 178, the gear element 192 is within theannular element 156 and in position to mesh with the tooth elements 168;the gear element 194 is within the annular element 170 and in mesh withthe teeth 174..

The gear elements 188, 192, are so proportioned and shaped relative tothe cooperating surfaces 152, 160, and the tooth elements 154, 168, thatthe tooth elements are operative for rotating the gear elements onetooth increment of movement, and thereafter the gear elements remainimmovable as controlled by the surfaces 152, 160, in accordance withknown characteristics of Geneva mechanisms. In the case of minute drum61, it is provided, as noted above, with a single series of digits of 1to 9, and 0, and accordingly tooth elements 154 at a single location areprovided so that in one revolution of that drum the gear element 188acting through the companion gear element 190 advances the ten-minutedrum 62 a corresponding amount which is one digit spacing, or of acomplete revolution of the latter.

A similar movement and control of the component 178 is provided, and inthis case two tooth elements 168 are provided, at each of diametricallyopposite points, so that at the end of six advancements of the drum 62which corresponds with six decades, the gear 192 is advanced an amountsuch that the gear 194 advances the hour drum 63 an amount representingone hour, which in this case is of a full rotation.

The construction also includes means for yieldingly retaining the drums62, 63 in fixed position between periodic. advancements. This meansincludes flexible radial arms 196 respectively between the drums 61, 62

and 62, 63, mounted on the shaft 138 against rotation and havinginclined elements 198 which engage in the gaps between the teeth 162,174. These arms 196 yield upon deliberate advancement of the drums, thisdavancement of the respective drums being in each case that representedby a single tooth spacing, the arms then interengaging in the next toothgaps.

The Geneva movement construction provides operative interengagementbetween the drums at a position closely adjacent the periphery of thedrums. This provides a long lever arm action, as contrasted with thegearing being positioned closely adjacent the hubs of the drums.

The advantages of the construction include greater accuracy and moresimplified control because of the additional leverage provided by thegreater distance from the axis of rotation; because of the greaterdistance from the axis of the gears, a given linear or peripheralincrement of movement results in a lesser angular movement as comparedwith the previous constructions in which the gears are closely adjacentthe axis. Another advantage is that static friction is more easilyovercome because of the greater leverage provided by the greater radialdistance from the axis.

The invention also includes novel means for presenting illuminatedindicia for observation, the illumination deriving from the lamp means14. Preferably the drums 61, 62, 63, are made of transparent plastic asrepresented in FIG. 6, and the lamp means 14 is positioned for directingthe light into the interior space of the drum unit 60, and to propagatethe light throughout the unit as through the openings 150. The outersurfaces of the elements 148 of the drums are provided with an opaquecoating 202 around the configurations forming the indicia 64, theseconfigurations including embossments 204 forming extensions of the bodyof the transparent material making up the drums, whereby theillumination is enabled to pass through the embossments making up theindicia, and not through the coating 202.

I claim:

1. Clock mechanism comprising a time indicating unit including asuccession of drums in turn including a first drum and at least onesuccessive drum,

means including main shaft means for mounting the drums for rotationabout the axis of that shaft means, the main shaft means including atleast a rotatable element and the first of the drums being secured tothat rotatable element for rotation therewith,

means operable in accordance with the passage of time for rotatablydriving said element of the shaft means and thereby rotating the firstof the drums,

the drums being of substantially greater diameter than the shaft means,

Geneva gearing for driving the successive drums from the first drum,including gear teeth on the drums at the periphery thereof and a gearcomponent between each two adjacent drums,

each gear component including a gear element meshing with the gear teethin the adjacent drum, the gear elements in all the gear components beingdisposed on axes remote from the axis of the main shaft means and closeto the gear teeth at the periphery of the drums, and

the drive transmission between the drums being initiated by the firstdrum and transmitted to the successive drums through the peripheries ofthe drums.

2. Clock mechanism according to claim 1 wherein,

the main shaft means also includes a fixed element, and

the mechanism including a radial arm for each gear component secured atone end to the fixed element of the main shaft means and mounting thegear component at its extended end.

3. Clock mechanism according to claaim 2 wherein,

the arms are disposed at transverse planes between adjacent elements ofadjacent drums,

the gear teeth on the drums are located on said adjacent elements of thedrums, and

each gear component includes axially spaced gears engaging the gearteeth on the respective ones of the elements of the adjacent drums. 4.Clock mechanism according to claim 2 and including, a radial armassociated with each successive drum secured at one end to the fixedelement of the main shaft means and having a flexible extended endyieldable in axial directions engageable with the teeth on therespective successive drum and thereby operative for yieldably retainingthose drums against rotation between positive movements of thesuccessive drums.

5. Clock mechanism according to claim 3 wherein, adjacent drums haveaxially intertelescoping elements, and the arms mounting the gearcomponents, which are essentially between the adjacent drums, areenclosed, considered as viewed radially, by the intertelescopingelements of the drums.

6. Clock mechanism comprising a plurality of coaxially mounted timeindicating drums and means for rotatably advancing the drums inaccordance with passage of time,

the drums having axially intertelescoping elements precluding elfectivepassage of light between drums,

the drums each including a web made up of spokes with spacestherebetween, the spaces forming openings extending axially throughoutthe drums,

the drums having peripheral elements made up of a background portion andtime indicating elements,

the background portion on the one hand and the time indicating elementson the other hand having different light transmitting characteristics toprovide visual contrast between the time indicating elements and thebackground portion.

7. Clock mechanism according to claim 2 wherein the drums include websin the form of spokes with openings therebetween forming continuousopenwork axially through the drums, and include peripheral elements oftransparent material, and opaque material on the outer surface thereofaround configurations forming time indicia whereby to enable passage oflight through the peripheral elements and through the time indiciaconfigurations, and light means illuminating the interior of the drums.

References Cited UNITED STATES PATENTS 2,355,514 8/1944 Deane et al.58l25 2,343,613 3/1944 Goldsmith, Jr. 58l25 2,459,107 1/1949 Johnson5819 2,748,560 6/1956 Clark 58-125 RICHARD B. WILKINSON, PrimaryExaminer E. C. SIMMONS, Assistant Examiner US. Cl. X.R. 58l25 C

